Jwin Portable mini Hi-Fi Stereo speaker system Detachable 2-piece portable stereo speaker system Connects to any standard (3.5mm) headphone jack. (No Power needed) Speaker Type: 3" Dynamic Wide Range Drivers. Frequency Response: 100-16,000 Hz. Speaker Impedance: 8 ohms Monitor Screen Magnetized Unit Size 3.7x4.5x3 (LxHxD)-Portable speaker system is very lightweight